Adaptive shut‐down of EEG activity predicts critical acidemia in the near‐term ovine fetus

Physiological Reports

Martin G. Frasch⁷  Lucien Daniel Durosier¹  Nathan Gold²  Mingju Cao¹  Brad Matushewski⁶  Lynn Keenliside⁵  Yoram Louzoun³  Michael G. Ross⁴ 

[1] Department of Obstetrics and Gynaecology, Department of Neurosciences, CHU Ste-Justine Research Center, Université de Montréal, Montreal, Quebec, Canada;Department of Mathematics and Statistics, York University, Toronto, Ontario, Canada;Department of Mathematics, Bar-Ilan University, Ramat-Gan, Israel;Department of Obstetrics & Gynecology, LA BioMed at Harbor-UCLA Medical Center, Torrance, California;Imaging Program, Lawson Health Research Institute, London, Ontario, Canada;Department of Obstetrics and Gynecology, University Western Ontario, London, Ontario, Canada;ORCID:orcid.org/0000-0003-3159-6321

关键词: Acidosis;    asphyxia;    ECOG;    EEG;    Fetus;    FHR;    hypoxia;    monitoring;   

DOI  :  10.14814/phy2.12435

来源: Wiley

【 摘 要 】

Abstract

In fetal sheep, the electrocorticogram (ECOG) recorded directly from the cortex during repetitive heart rate (FHR) decelerations induced by umbilical cord occlusions (UCO) predictably correlates with worsening hypoxic-acidemia. In human fetal monitoring during labor, the equivalent electroencephalogram (EEG) can be recorded noninvasively from the scalp. We tested the hypothesis that combined fetal EEG – FHR monitoring allows for early detection of worsening hypoxic-acidemia similar to that shown for ECOG-FHR monitoring. Near-term fetal sheep (n = 9) were chronically instrumented with arterial and venous catheters, ECG, ECOG, and EEG electrodes and umbilical cord occluder, followed by 4 days of recovery. Repetitive UCOs of 1 min duration and increasing strength (with regard to the degree of reduction in umbilical blood flow) were induced each 2.5 min until pH dropped to <7.00. Repetitive UCOs led to marked acidosis (arterial pH 7.35 ± 0.01 to 7.00 ± 0.03). At pH of 7.22 ± 0.03 (range 7.32–7.07), and 45 ± 9 min (range 1 h 33 min–20 min) prior to attaining pH < 7.00, both ECOG and EEG amplitudes began to decrease ~fourfold during each FHR deceleration in a synchronized manner. Confirming our hypothesis, these findings support fetal EEG as a useful adjunct to FHR monitoring during human labor for early detection of incipient fetal acidemia.

【 授权许可】

CC BY   
© 2015 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

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